Sensitization of Lanthanide Luminescence in Heterotrinuclear PtLn_2(Ln = Eu, Nd, Yb) Complexes with Terpyridyl-Functionalized Alkynyl by Energy Transfer from a Platinum(II) Alkynyl Chromophore

摘要

The preparation and characterization of the mononuclear complexes cis-Pt(dppe)(C ident to CPhtpy)_2 (1) and cis-Pt(dppp)(C ident to CPhtpy)_2 (5) (dppe = 1,2-bis(diphenylphosphino)ethane, dppp = 1,3-bis(diphenylphos-phino)propane, HC ident to CPhtpy = 4'-(4-ethynylphenyl)-2,2':6',2"-terpyridine) and the corresponding PtLn_2 (Ln = Eu, Nd, Yb) heterotrinuclear complexes by incorporating the precursor 1 or 5 with Ln(hfac)_3-(H2O)_2 are described. 1 and 5 exhibit intense, long-lived room-temperature phosphorescence, originating probably from an admixture of ~3ILCT (pi-> pi*(C ident to Cphtpy)) and ~3MLCT (d(Pt) -> pi*(C ident to CPhtpy)) triplet states, which qualifies them as favorable energy donors to facilitate Pt -> Ln energy transfer in the corresponding PtLn_2 heterotrinuclear complexes. As anticipated, sensitized lanthanide luminescence in PtLn_2 heterotrinuclear complexes is attained through efficient energy transfer from Pt~(II) alkynyl chromophore based ~3MLCT and ~3ILCT triplet states.